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Variation of Preferred Orientation in Oriented Clay Mounts as a Result of Sample Preparation and Composition

Published online by Cambridge University Press:  01 January 2024

R. Dohrmann ,
K. B. Rüping ,
M. Kleber ,
K. Ufer  and
R. Jahn
R. Dohrmann*
Affiliation:
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Hannover, Germany/ Landesamt für Bergbau, Energie und Geologie (LBEG), Stilleweg 2, D-30655, Hannover, Germany
K. B. Rüping
Affiliation:
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Hannover, Germany/ Landesamt für Bergbau, Energie und Geologie (LBEG), Stilleweg 2, D-30655, Hannover, Germany University of Halle-Wittenberg, Institute of Agricultural and Nutritional Sciences, D-06108 Halle (Saale), Germany
M. Kleber
Affiliation:
Oregon State University, Department of Crop and Soil Science, Corvallis, OR 97331, USA
K. Ufer
Affiliation:
TU Bergakademie Freiberg, Institute of Mineralogy, D-09596 Freiberg, Germany
R. Jahn
Affiliation:
University of Halle-Wittenberg, Institute of Agricultural and Nutritional Sciences, D-06108 Halle (Saale), Germany
*
* E-mail address of corresponding author: reiner.dohrmann@lbeg.niedersachsen.de
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Abstract

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In X-ray diffraction (XRD) analysis, preparation of oriented clay specimens enhances their 00l reflections by arranging basal surfaces parallel to the specimen surface. In one-dimensional modeling of XRD intensities, degree of preferred orientation is one of the variable parameters and a user may choose different σ* values for different minerals. The usual assumption is, however, that the layers of all clay minerals that are present exhibit a similar degree of preferred orientation to that of the clay mineral flakes parallel to the basal plane. If the orientation of individual clay minerals is significantly different, and if this is not taken into account, the relative proportions of the constituent minerals cannot be modeled accurately. The actual or so-called ‘preferred’ orientation is a potentially large source of error in any attempt at quantitative XRD analysis because it cannot be assumed to be constant among different minerals and may also vary as a result of pretreatment. In the present study the influence of sample composition and sample pretreatment on the degree of preferred orientation was determined using the parameter σ*. A statistical parameter was calculated to determine and ensure the reproducibility of σ* measurements. The most important result was that, when mixed together, clay minerals influence each other in terms of the degree of preferred orientation. Among individual samples, the degree of preferred orientation can be different for each clay mineral. The power of sonication used in sample pretreatment of a pure kaolinite and a pure illite had no significant influence on the degree of preferred orientation. The changes in intensities upon variation of the tilting angle (χ) allowed for calculation of σ* of smectites in pure samples, in admixtures, and in samples treated in two different ways (air-dried and glycerol-intercalated), which is reported here for the first time. Smectites are very fine grained with flexible morphology which is believed to be the reason for their tendency to exhibit poor orientation (σ* = 22°); further research is required to establish whether this is a general feature of smectites. After glycerol treatment a soil smectite showed a slightly better orientation compared to the air-dried pattern. The results of the study illustrate the difficulty of predicting changes in preferred orientation of clay mineral admixtures, even if non-platy minerals such as clay-sized quartz are added. In general, σ* decreased when non-platy minerals were added, which is explained by changes in geometry of the specimen. Not all clay minerals, however, showed simultaneous changes in their orientation behavior.

Keywords

Clay MineralsOriented MountsPreferred OrientationQuantitative Phase AnalysisSigma*XRD
Type
Research Article
Information
Clays and Clay Minerals , Volume 57 , Issue 6 , December 2009 , pp. 686 - 694
Copyright
Copyright © The Clay Minerals Society 2009

References

Amelung, W. and Zech, W., 1999 Minimisation of organic matter disruption during particle-size fractionation of grassland epipedons Geoderma 92 73–85 10.1016/S0016-7061(99)00023-3.CrossRefGoogle Scholar
Bergmann, J. Friedel, P. and Kleeberg, R., 1998 BGMN — a new fundamental parameter-based Rietveld program for laboratory X-ray sources, its use in quantitative analysis and structure investigations Commission of Powder Diffraction 20 5–8 International Union of Crystallography, CPD Newsletter.Google Scholar
Brosche, K.-J., Gehrt, E., and Klosa, D. (1998) Exkursionsführer zur 17. Sitzung des AK Paläoböden 1998 in Braunschweig, Germany, pp. 18 ff.Google Scholar
Dohrmann, R., 1997 Kationenaustauschkapazität von Tonen — Bewertung bisheriger Analysenverfahren und Vorstellung einer neuen und exakten Silber-Thioharnstoff-Methode Aachen, Germany RWTH Aachen 237 pp.Google Scholar
Fesharaki, O. García-Romero, E. Cuevas-González, J. and López-Martínez, N., 2007 Clay mineral genesis and chemical evolution in the Miocene sediments of Somosaguas, Madrid Basin, Spain Clay Minerals 42 187–201 10.1180/claymin.2007.042.2.05.CrossRefGoogle Scholar
Jahn, R. and Kunold, W., 1997 Exkursion D3; Querschnitt durch den Hegau und seine Randbereiche Mitteilungen der Deutschen Bodenkundlichen Gesellschaft 82 213–250.Google Scholar
Köster, H.M., 1979 Die chemische Silikatanalyse: Spektralphotometrische, komplexometrische und flammenspektrometrische Analysenmethoden Berlin Springer Verlag 10.1007/978-3-642-67275-0 196 pp.CrossRefGoogle Scholar
Lippmann, F., 1970 Functions describing preferred orientation in flat aggregates of flake-like clay minerals and in other axially symmetric fabrics Contributions to Mineralogy and Petrology 25 77–94 10.1007/BF00389778.CrossRefGoogle Scholar
Moore, D.M. and Reynolds, RC Jr., 1997 X-ray Diffraction and the Identification and Analysis of Clay Minerals New York Oxford University Press 378 pp.Google Scholar
Reynolds, RC Jr., 1985 NEWMOD: a computer program for calculation of one-dimensional diffraction patterns of mixed-layer clays 9 Brook Rd., New Hampshire 03755, USA R.C. Reynolds.Google Scholar
Reynolds, RC Jr., 1986 The Lorentz-Polarization factor and preferred orientation in oriented clay aggregates Clays and Clay Minerals 34 359–367 10.1346/CCMN.1986.0340402.CrossRefGoogle Scholar
Reynolds, RC Jr., Pevear, D.R. Mumpton, F.A., 1989 Principles and techniques of quantitative analysis of clay minerals by X-ray powder diffraction Quantitative Mineral Analysis of Clays Boulder, Colorado, USA The Clay Minerals Society 171.Google Scholar
Rüping, K., 2007 Quantifizierung von Bodentonmineralen auf der Basis einer Komplexen Mineralogischen Phasenanalyse Halle, Germany Halle-Wittenberg University 140 pp.Google Scholar
Schmidt, M.W.I. Rumpel, C. and Kögel-Knabner, I., 1999 Evaluation of an ultrasonic dispersion procedure to isolate primary organomineral complexes from soils European Journal of Soil Science 50 87–94 10.1046/j.1365-2389.1999.00211.x.CrossRefGoogle Scholar
Schulze, D.G., Amonette, J.E. Stucki, J.W., 1994 Differential X-ray Diffraction Analysis of Soil Minerals Quantitative Methods in Soil Mineralogy Madison, Wisconsin, USA Soil Science Society of America 412–428.Google Scholar
Taylor, R.M. and Norrish, K., 1966 The measurement of orientation distribution and its application to quantitative X-ray diffraction analysis Clay Minerals 6 127–142 10.1180/claymin.1966.006.3.01.CrossRefGoogle Scholar
Treacy, M.M.J. Newsam, J.M. and Deem, M.W., 1991 A general recursion method for calculating diffracted intensities from crystals containing planar faults Proceedings of the Royal Society, London A433 499–520 10.1098/rspa.1991.0062.Google Scholar
Tributh, H. and Lagaly, G., 1986 Aufbereitung und Identifizierung von Boden- und Lagerstättentonen. I. Aufbereitung der Proben im Labor GIT-Fachzeitschrift für das Laboratorium 30 524–529.Google Scholar
Ufer, K. Kleeberg, R. Bergmann, J. Curtius, H. and Dohrmann, R., 2008 Refining real structure parameters of disordered layer structures within the Rietveld method Zeitschrift für Kristallographie Supplements 27 151–158 10.1524/zksu.2008.0020.CrossRefGoogle Scholar
Whitton, J.S. Churchman, G.J., 1987 Standard methods for Mineral Analysis of Soil Survey Samples for Characterization and Classification NZ Soil Bureau Scientific Report 79 Lower Hutt, New Zealand DSIR.Google Scholar
Zevin, L. and Viaene, W., 1990 Impact of clay particle orientation on quantitative clay diffractometry Clay Minerals 25 401–418 10.1180/claymin.1990.025.4.01.CrossRefGoogle Scholar